Try using the space key to complete the alias, instead of ctrl-space - seems to work for me, though according to the help, you'd think ctrl-space would be required! Perhaps ctrl-space applies when you type less than the name of the alias. On the auto-complete tab, you can turn off whether you get automatic completion for aliases or not.

I just tested this and got the same result. I'm looking into it. In the meantime, there is a function called "expand-alias", which is bound to Ctrl+Shift+O in the CUA emulation. That will expand the alias without any other form of completions getting in the way.

Interestingly, this is not mentioned in the User Guide. So, I'll make sure we get that updated too.